Torque shaft



Feb. 5, 1946. D. w. scHAE-FFER 2,394,490

TORQUE SHAFT {Fi-led July 1, 1944 y sheets-sheet 1 ATTORNEY Feb. 5, 1946. D. w. scHAr-:FFER v 2,394,490

` TORQUE SHAFT Filed July 1, 1944 2 sheetsQsheet 2 Patented Feb. 5, 1946 UNITED STATES PATENT FFICE- 52394,496 'riiom SHAFT onald*V Schaeit'er,` liayton,- Oxio Atroi'ioetro .fuir 1, 1944, seriali ifo: M652 (Cl: f4-57) Claims;

This invention relates to' anintenal cornbii: tion engine, and particularly` to an engine Where-' in the reciprocating motion' o'f the connecting rod of the pistons of the engine are translated: into a rotary motion for transmitting power to a driven device. w

In reciprocating interi'al combustion engines' of the' type wherein opposed pistons move in axial alignment, and are" interconnected by means of a single connecting rod extending be` tween the opposedA pistons, vvherein the motief ment of the connecting rodisu'se'd to'tran'slate the reciprocating motion of the pistons intoA a rotary motion', it is necessary to prevent the connecting rod from rotation preferably by the' bearing means that support the connecting rod. Under such circumstances thel bearing rn'ea'ris" absorb a continuous torque effort as applied to the connecting rod by thel translation of the te? ciprocating motion into a rotary motion which' produces considerable wear o n the bearing'. The" usual odd shapes that are givento a connecting rod to prevent rotation thereof inthe bearingi has not provided for a balanced bearingV load upon the entire bearing surface, and therefore' uneven load distribution is carried by the bear# ing surface on the' connecting rod and on the' bearing surface of theV stationary bearingr sothat uneven Wear has occurred on the reciprocating member and on ther bearing surface.v

It is therefore an object of this invention to provide a bearing"A surface for a reciprocating member that moves' in' a stationaryl bearing to which a rotary torque is app'liedthat will evenly distribute the torque load over the: entire bear`4V ing surface.'

Another object of the invention is4 to provide a bearing surface upon" a reciprocating partthat moves in a stationary*bearingl niernberthat is in the form of a spiral of Archimedeswhere'b'y the"v torque load applied'- upon the reciprocating part is evenly distributed over the entire" bearing surface.

It is still a further object of" thejinventioh to provide means" for distrbtingfthe torque load upon a torque shaft throughout the entire length of the shaft by means of' a-mernber that is placed within theshaft for conducting the load of the torque applied upon the'shaft throughout a length of the' member; and for picking' unthe load from the shaft at various-pointstthroughot the length thereof.'

stru another object of the invention' 1ste proj#v vide a torque s haftthat is' hollowhavin'g a menti ber that is' placed Within the hollow" sha-ft" in prevent ioean d torque load in the Sh stru' etno-ther 'o'bjeotof trieirifveritiorr it yprof v'rde et torque s heft rrr ooorderioe' with tutti two" mentionedobectsfwnerern the member t at is" positioned rrr tire no1- low tor'q'l YstrettaA in tire forro of e neurr t'ht--iirifposi-uve with the torque shaft at various'i'terv sj aioig h of tuerkei-trottoir trie 10er;

ber that must be held from rotation, and which should be of substantial strength. The principals of the invention therefore are not limited to the particular type of apparatus disclosed in thedrawings, but are applicable to any torque Shaft.

tracll 38 are all more Vparticularly set forth in my copending application Serial No. 451,281 filed ln Figure 1 there is disclosed one power unit of a gasoline engine of the four-cycle type that is adapted to be associated with a plurality of other power units disposed radially abo'utda-cen-v tral drive shaft. Each of the powerunits isV p'io- October 8, 1942, and does not constitute a part of the invention of this application.

It will therefore become apparent that When Y the pistons reciprocate axially within the rotatable member I2 that a torque is applied upon the connecting rod 23 attempting to force the same to rotate in thefbearings 26' and 26a, and

' therefore applies La force upon the bearing sur'- vided with a rotatablemember that has a gear.

integral therewith that is adapted to be in oper-f* Y With the rotatable member moving in the direction ofthe arrow 39 shown in Figure 2, the torque thrust Yapplied upon the connecting rod 23 will Vv-be inlthe direction'of the arrow placed uponV the e connecting rod inFigure 2. The surface contour Y of t'hemconnectingY rod 23 thus will determine the manner vofload distribution to the surface of the Y ative association with a gear secured to theV central drive shaft whereby rotation of the rota able member on the pluralityV of power'units causes rotation of the drive shaftfcrdriving anyi l I device desired. Y

Each of the power units I consists of a pair of cylinders I 5 and Ia that areY disposed in axial alignment andare carried ina suitable ,frame Vstructure I6. Each ofthe cylinclers'."i5v receives a Vpiston I'I land.Ilcrfresp,ectively wherebyV the power chainlmers,I8 and 4IS'a are provided in the cylinderse|5 andA |5d..1`he .,cylindrslvand I5a are provided with the'usualheads I 9 and lila.`

respectivelyjfor,closing the endof the cylinder andY forpreceivingathe spark plugs 23 and 23a..

The .heads I9 and II ilav are provided Yvvithl inlet valves 2I andf2la' 1and .vvitl'i outlet valvs`22 and 22a respectively. 'l The pistons II and e y of V a connecting rod 23 that rigidly connects. the piston in spaced relationship with respect to one another and causes themto vreciprocate in unison, this connecting rod vv2234 being more fully describedhereinafter. y

The rotatable member" i2 is disposed around theconneeting rod 23 "and is positioned between the inner ends "26 andlla, offthetcylinders I5 and I5@ respectively. The member VI2l "ist'sutably i I 'Id are'connecte'd by means faces that produces friction when the connecting Y rod 23 reciprocates'inthe bearings 26 and 26a.

torqu'eflapplie'dV tothe connecting rod tending to r bearing 2s.

bearinged in the ends 24 Yand. 24a bynreans of V the ball bearing membersl25` and 25a.

n`In' order to 4change the reciprocating .motion Y i ofthe connectingrod 23einto a rotaryf'lmotion forrdriving a drive shaft, oapiston Bifs 4slidably disposed withina cylinder bore 3|. providedjin thewrotatablermember t2. The piston 39 is suitably-secured to-thefeonnecting rod 2:5'A andY is y adapted tozjreciprocate axially within the cylinder borea3l. `The piston rSii ^isv.,prev ented from `As illustrated `Figures San'dufl,V theexterior Y surface Yof the connectingirod'r23 is provided with a special contour that will providefor'lo'ad distribution'equally4 overfthe entiresurface ofthe connecting rod bearing surface. `The torque `applied upon the connecting rod 23 by movement of thepiston 30 in thecylinder-S I isin the'direcf' tion of the'arrow shown on FigureS. f

IThe-development of thecontourf ofthe surface Sil .on the connectingfrcd 23i5 shown more specifv icallyn Figure 4. In preparingthe development on the surface 50 of the connecting rod 23, alpluralityof equal distantly spaced circles 5I are'constructed about an-axis 52', which represents the axis of the connecting rod 23. YThe circurnfer' enceY of thecircles varemthen divided into equal arcsbythezradii 53. The' intersecting points between'the Ecircle`s5l\ andthe radiiA 53 are then n joined seas Yto produce asmoothlyfiiowing curved surface ertending from the outermost circle to theinnermost circle, which curveV includes onehalfthe circumference'of. the circles 5I and thus Y represents onehalf.-theY circumferencel of theYV connecting-rod 21hY Thefsurface 58 of thev oo nnecting rod i231 is'thus shaped in the Vform of a spiral wherein.,the surface moves outwardly from the axis'orfpint' of generationgequal distancesV foreach predetermined degreeo rotation of the rotation Vein' Vthe'cylinder 3I bythe connecting rod 23 that'has a special external shape Aprovided thereon to preventits rotation in the bearings but 1- whichI canfreciprocate inv Vthe o bearings 26 andi/26a.

The piston memberV se "carries a l'cylindrical' member 32 that is postonediwithin av-bearing ofv the Vpiston 3f).V The cylindrical memberf32 Vis o sleeve 33 provided atv a right angle .totheaxis i as1caused by apair of cylindricallrmembers'll e and 35i-that have their axes parallel totheV axis of the member 32.

` The cylindrical members. and t5 arelprovided withertensions 36 and 31 respectively that aregadaptedto engage a track 38 providedin the cylinder wall 3|. v The trackp38'has a configurationin the nature-ofaffigure 8;.and is continuous from one end of the cylinder 3I-to the opposite end thereof so that byreciprocation ofthe piston 30 `inthe cylinder `3l theextensions 35 and -31- on; the-piston V-3Ilf will followthe traclg `38 and thereby cause rotationof the rotatable meml ber I2. The particular construction and arrangegeneratingv point yabout theaxiasothat the spiral isinelecta Spiralof Archimedes. VThe sur` 'I .face 5Uaon the opposite .side of the connecting rod is generated in the same manner'.

l 'Vv'hen .the surfaces 5I)V and 50a are 'generated inthe manner heretofore 'descrbed, anyf VVtendency .tovvardlrotation of Ythe connectingfrodl 23 aboutthe axis Vr512 thereof, `vvillgcause `anypoint on fthe" surface `of the connectingrod to move radially outwardlyla'distance equal to the movement ofy each-and every otherV point on the'same surface. Therefore, any tendency/toward rotationlof the Vconnectingjrod 23fiscarried by the entire bearing'surfa'ce area of the'connecting rod.

It will of course. be understood thatY thebearing 25 Ahasth'e surfacethereoffformedto a contour which matches that -of the connecting rod 23so thatthe connecting rod can reciprocate inthe bearingf'26but cannot rotate-thereim Since allV torque applied upon the connecting rod 23, is in.

the directionfof the arrow shown Iinf'li'gurer4', it

will be apparentthatthe'lips 54 onbppositesides f ofv theconnectingrod '23 do not carry.. any.l torque load, and in fact if there is any rotative effect bel-` meen the connecting rod 23 and the bearing sur.- face for the same, the lips E on the connecting rod 23 will separate from the corresponding lips in the bore 2li-j With the torque load applied to the connecting rod evenly distributed overthe entire bearing surface thereof while reciprocating from the bore Z6, the life' of'the bearing surface isgreatly increasedi Y Y TheA torque load applied upon the connecting rod' V23 in the engine illustrated in Figures l and 2i is relatively high, and it is desirable that' the connecting rod, orl torque shaft, should have its strength increased to as great an extent as` possible without causing the use of extremely large diameters inthe connecting rod to obtain the de'-` sired'strength to resist' the torque effort applied upon it. Under normal circumstances, the torque e'ort is applied upon a torque shaft at one end thereof, the torque being transmitted to a driven device at the opposite end so that the torque loa-d is more or less centralized at' the point of application of the load upon the torque shaft and the point of transmission thereof ton the driven device, which torque ten-ds' toward a twisting of the entire torque shaft.

In this invention, however, the connecting rod 23', or torque shaft, is constructed in the form of a hollow tube wherein there is placed a member in the form of a helix to absorb the torque applied to the torque shaft and evenly'distribute the torque loa-d over the entire length of the torque shaft rather than permitting the aforementioned conditions of localized torque effort to exist.

As aforementioned', the connecting rod 23 is a hollow substantially tubular member that is provided with thel exteriorv surface shaped as heretofore described. When the tube is thus formed, there is provided the ledges 6l]J on opposite sides thereof that are formed when the tube is shaped to the aforementioned configuration. Also, interior surface 6| of the hollow tube forming the connecting rod 23- is of substantially the same con'guration as the surfaces 55 and 5ta of the connecting rod tube 23.

The rigid member 52' is placed within the connecting rod tube 2'3 with the axis thereof coinciding with the axis of the connecting rod tube 23'. The member G2 has a n 63 positioned radially therefrom' and extending from one end of the tube to the other, this fin being in the form of a helix surrounding the cylindrical body 34 of the member 62.

The helix S3 is provided with an exterior' surface S5 that conforms at least in part tothe innerV surface 6! of the connecting rod tube 23 so that the surface 65 of the helix will be in surface engagement with the inner surface t l' of the tubular connecting rod 23 from end to end thereof. Also, the helix 63 is provided with recess portions [i6 that engage the ledges EU provided in the inner surface 6I of the tubular connecting rod 23'. The helix 63' thus engages the ledges 6d each 180 of rotation about the axis of the connecting rod. In addition, the helix is shaped' so thatY a torque applied on one end thereof Ahas the tendency to unwind the helix inthe manner of a coil spring.

When the member 62' is placed in the hollow connecting rod tube 2.3', it is placed therein as a press fit so that the surface 65 ofA thev helix is in full surface engagement with the surface 6I of the. connecting rodtube 23, and the recess portions BB on the helix are' in positive engagement with the ledges 6U. Thus, when a torque effort isL applied' to the connecting rou: 23 inthe direc tion' of the-' arrow shown on Figure 4, the torqlie` is transmitted directly to the member 62 from the helix 63, and' since the helix'- 63 engages' ledges at periodic intervals along` the length of the oonnecting rod 2, itA will be apparent thatthel torque' effort applied tothe' connecting rod tube will' be transferred to the helix 63 and the member 62 at periodic intervals along the helix 63,- thusabsorbing the torque effort along the entire con'- ne'cting rod tube 23. The toi-quel effort applied to the connecting rod tube 23 has the tendency to uncoil the helix 63, which being inapressfit engagement with the surfaces El" ofthetuzbe 23, supports the tube throughout the entire length thereof and thus increases the strength ofthe' connecting rod tube 23. isi-ncev the helix 63 .engages the connecting rod tube 23 intermittently throughout its length; it is not necessary for the torqueeffort of the tube to be transmitted coin-- pletely from end to end thereof unsupported, but rather theV torque effort upon the tube 23 will be picked up periodically by the helix' and transmittedl tothe member 62 thereby eliminating'. lon-g lengths of unsupported torquetube.

In Figures (iA and 7 there is illustrated the use of the strengthening helix in a common torque shaft, which in this instance is a torque tube. The torque tube 'mi isconnected at one end. to a power source such as an electric motor Tl, and is connected to a driven mechanism 'l2 at the oppo site end thereof.v 'I'heto-rque` tube 1l) has anginternal bore T3 that has the surfaces thereof arranged excentrically to provide the ledges 'f4 on opposite sides of the bore 13; A member `62ay similar to that heretofore described is inserted in the bore 73, as a press 't therein, so that the surface 65a ofthe helix 63a engages the bore 13, and the lips 65a on the helix 63a engage the ledges T4'. The functioning of the member 52a within the torque shaft, or tube lll, is the same as heretofore described with regard to the functioning of the member 6-2 in the connecting' rod tube 23.

While the apparatus disclosed and described' herein constitutes a preferred form of the invention, yet it will be understood that the apparatus is capable of alteration without departing. from the spirit of the invention, and that-modiflcations that fall within the scope of the appended claims are intended to be included herein.

Having thus fully described my invention, what I- claim as new and desire to secure by Letters Patent is:

1. In combination, apower shaft supported' in a bearing member, a load bearing surface on said power shaft parallel to the axis of saidv shaft and disposed in the form of a spiral about the axis of the power shaft with the axis of the spiral coinciding with the axis of the shaft, and a surface in said bearing complementary to said surface on said shafts of the power shaft for cooperating with the surface on the power shaft to thereby support the same.

2". Incombination', a power shaft, bearing means for supporting said power shaft for reciprocation therein, said power shaft having at least a part `of the exterior surface thereof disposed parallel to the aids of said shaft in an arrange-i ment of a spiral about the axis of the power shaft with the axis of the spiral coinciding with the axis of the shaft, and a surface in said bearing complementary to said surface on said shaft' to cooperate with the said spiral surfaceY onl said shaft' to support said shaft insaid bearing.

3. In combination, a power shaft, bearing means forsupporting said power shaft for re ciprocation therein, said power shaft, having Vat least a part of the exterior surface thereof ing with the axis of the shaft, and av surface inV said bearing complementary tor said surface on said shaft to cooperate with the said spiral surface on said shaft to support said shaft in said bearing, to prevent rotation of said shaft inisaid bearing Vbut with complete freedom of axial movement therein. -Q 4. In combination, a power shaft having at least a part of the exterior Vsurface thereof dis-` posed parallel to the axis of the shaft and arranged in the form of avspiral about the longitudinalaxis Vof the shaft with the axis of the spiral coinciding with the axis of the shaft, said spiral surface having a contour generated by a Ypoint moving radially outwardly from the axis of thel power shaft a predetermined distance for each degree of rotation thereof about the axis of the power shaft, and a bearing having a spiral surface therein generated in the same manner as the spiral surface on said shaft forcooperating therewith to support said power shaft.

. 5. In combination, la power shaft having exterior, load bearing surfaces extending longitudinally thereof parallelto the axis of the shaft, each of said surfaces being arranged in the form of a kspiral about the longitudinal axis of the Y shaft with the axis of the spiral coinciding with the axis of the shaft, said spiral surfaces each, having a contour generated by a point moving radially outwardly from the axis of the power shaft a predetermined distance for each degree of rotation thereof about the axis of the power shaft Vand extending 180 about said shaft, a bearing member for said shaft, and a spiral surface in said bearing generated in Ythe same manner as the spiral surface on said shaft for cooperating therewith to support said power shaft thereon, to prevent rotation of said power shaft' in said bearingrand evenly distribute a torque load applied vto the shaft over the entire contacting spiral surfaces between said shaft and said bearing. f j y 6. In combination, a hollow torque shaft having an inner surface parallel to the axis ofthe shaft and arranged in the form of a spiral -with the axis of the spiral coinciding with the axisrof the shaft whereby to form a ledge' extending'longitudinally of said shaft in said inner surface, and

a rigid member positioned within said hollow torque shaft having a helix thereon engaging the ledge on the inner surface of saidtorque shaft periodically along the length thereof, whereby tov transfer torque effort upon said torque shaft to` 7. In combination, a hollow power shaft adaptsaid member. f

ed for movement relative to a supporting bearing surface and adapted to have torque applied thereto tending to rotate the power shaft relative to the bearing surface, a bearing member Yhaving i a bearing surface for supporting the power shaft, said power shaft having at least the Vsurface n thereof for supporting the shaft upon the bearing arranged in theform of a spiral'about the; axis ofwthe power shaft with the spiral moving outwardly relative to the axis of the power shaft a predetermined distancek for each degreeof -rotation thereof about the axis of the shaft, and am surface on said bearing having a similarly shaped spiral Varrangement to cooperate with the sup'-l porting surface on the shaft and thereby distribute the torque load upon the shaft over the contacting surfaces of the shaft and the bearing, saidv spiral surfaces extending approximately 180 of rotation of said shaft whereby to form a ledge,V

extending longitudinally of s'aidcshaft vin said inner and outer surfaces, and a rigid member positioned within said hollowY torqueshaft having "a helix thereon engaging thev ledgeson the innerY Y V surface of said torque shaft periodically along the length thereof, Vwhereby to transfer torque s effort upon said torque shaft to said member,

the helix on said member having a direction of rotation thereon opposite to the directionV of j torque applied to said torque shaft whereby to` j tend to'unwind said helixby lthe torque eifort applied upon said shaft and thereby transferring the torque effort vfrom the vshaft to the said member. Y

8. In combination, a torque shaft having a hollow interior extending longitudinally. thereof: whereby to'form an interior surface in the torque Y shaft, said interior surface of said torque shaft comprising a plurality of arcuately shaped sur-v face areas disposed off center with regard Vtoone f another and parallel to the axis of the shaft to form ledges extending longitudinallyofthe shaft, and a rigidvmember positioned within said shaft having a helix thereon engaging said ledges periodically along the llength Vof Y said`shaft .whereby to transmit the torque effort applied. to

the shaft to the said member. n

9. In combination, a hollow power shaft adapte ed for movement relative to a supporting bearing surface ,Y and adapted to have torque applied thereto tending to rotate the power shaft relative' to the bearingsurfac'e, a bearing member having a bearing surface for supporting the power shaft,V said power shaft havingY at` least the surfacef thereof for supporting the shaft upon the bearing arranged in the form of a spiral about the axis of the power shaft .with the spiral moving Voutwardly relative to the axis of the power shaft a predetermined distance for each degree of rota-V tion thereof about the axis of the shaft, and a surface on said bearing having a similarly shaped spiral Varrangement to cooperate with the supporting surface on the shaft and thereby'distrib-V ute the torque load upon the shaft overthe contacting surfaces ofthe shaft and the bearing,

said spiral surfaces extending approximately i'Y of rotation of saidshaft vwhereby to form a ledge extending longitudinally of said shaft in said inl ner and outer surfaces, and a rigid member posi- V tioned within said hollow torque shaft having a; Y

helix thereony engaging the ledges Yon the inner surface Vof said torque shaft periodically along the length thereof, whereby to transfer torque effort upon said torque` shaft `to said member.

,10. In combination, a hollow torque shaft having an inner surface parallel to thev axis of the shaft spirally generated from the axis of the shafty wherebyto form a ledge in the inner surface' ex- A. tending longitudinally along the shaft, and a rigid l member positioned within said hollow torque shaft having a helix thereon engaging the ledge on the inner surface of the torque shaft periodically along'the length thereof and woundrin a direction to expand when the torque is applied thereto Y by said torque shaftf whereby Vtorque is transferred from the torque'v shaft to said member. 

